package com.atguigu.cart.interceptor;

import com.atguigu.cart.to.UserInfoTo;
import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberResponseVo;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

@Component
public class CartInterceptor implements HandlerInterceptor {

  public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

  /**
   * 方法执行之前
   *
   * @param request
   * @param response
   * @param handler
   * @return
   * @throws Exception
   */
  @Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    HttpSession session = request.getSession();
    MemberResponseVo memberResponseVo = (MemberResponseVo) session.getAttribute(AuthServerConstant.LOGIN_USER);
    UserInfoTo userInfoTo = new UserInfoTo();
    //1 用户已经登录，设置userId
    if (memberResponseVo != null) {
      userInfoTo.setUserId(memberResponseVo.getId());
    }

    Cookie[] cookies = request.getCookies();
    if (cookies != null && cookies.length > 0) {
      for (Cookie cookie : cookies) {
        //2 如果浏览器中已经有user-Key，则直接设置
        if (cookie.getName().equals(CartConstant.TEMP_USER_COOKIE_NAME)) {
          userInfoTo.setUserKey(cookie.getValue());
          userInfoTo.setTempUser(true);
        }
      }
    }

    //3 如果浏览器没有user-key，我们通过uuid生成user-key
    if (StringUtils.isEmpty(userInfoTo.getUserKey())) {
      String uuid = UUID.randomUUID().toString();
      userInfoTo.setUserKey(uuid);
    }

    threadLocal.set(userInfoTo);
    return true;
  }

  /**
   * 业务执行之后
   *
   * @param request
   * @param response
   * @param handler
   * @param modelAndView
   * @throws Exception
   */
  @Override
  public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
    UserInfoTo userInfoTo = threadLocal.get();
    //如果浏览器中没有user-key，我们为其生成
    if (!userInfoTo.getTempUser()) {
      Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
      cookie.setDomain("gulimall.com");
      cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
      response.addCookie(cookie);
    }
  }
}
